This invention relates to a rotational slide type mechanical pencil in which a slider holding a lead is retractable and extendable in and out of a mouth tip of the mechanical pencil body.
A rotation type of lead feeding mechanical pencil is a well known type of mechanical pencil. However, the rotation lead feeding mechanical pencil has the following disadvantages:
(1) Both hands are required to advance and provide a lead at the mouth end of the mechanical pencil;
(2) An axial body member must be rotated, confirming an extending length of the lead;
(3) A new lead must be inserted from the mouth tip into the mechanical pencil;
(4) Since a lead is liable to be broken in a new lead supply, thin lead is not used.
Due to the above disadvantages, the rotation lead feeding type mechanical pencil is not used as often as in the past. Instead, recently, a step-by-step knocking type mechanical pencil has been successfully introduced. However, the knocking type mechanical pencil has the significant disadvantage that a design thereof deteriorates due to the utilization of a knocking cap. In order to overcome this, a slide cap type mechanical pencil has been provided. However, this slide cap type mechanical pencil has also disadvantage that since a reciprocatingly movable cap per se is moved forward and backward for every knocking, the cap is contacted to the gripping hand and it is difficult to handle it.
On the other hand, the rotation lead feeding type mechanical pencil is still manufactured and used and large companies still make the rotation lead feeding type because of the superiority of its design. Therefore, a rotation type retains an image of first class article.